Submersible robots are used for various purposes in the prior art. Autonomous and remotely controlled robots can take many forms and sizes and have been adapted for numerous purposes. Some known designs are used only for surveillance and monitoring, and are not able to interact directly with other objects, on a physical level. Such robots include so-called ‘snake robots’, which move with an eel-like or fish-like motion. Other known designs include gliders using buoyancy driven propulsion for mapping and monitoring, ROVs (remotely operated vehicles) and AUVs (autonomous underwater vehicles) with manipulators for physical interaction with other objects, such as robotic arms holding grasping mechanisms and other tools. The ROV or AUV must provide a stable base in order to support the arm, and hence such vehicles are relatively large and cumbersome. Gliders are limited in accuracy when it comes to guidance, navigation and control, and are only able to work effectively as they undulate downwards or upwards. This makes it difficult to use underwater manipulator robots when it is required to manipulate an object in a small space, or when the access to the working area is narrow.